What is kairuku grebneffi?

Kairuku grebneffi is an extinct species of penguin that lived during the late Oligocene epoch around 25-27 million years ago. The species belongs to the family Spheniscidae and is one of the largest penguin species ever discovered, with an estimated height of around 4 feet (1.2 meters) and weight of up to 88 pounds (40 kilograms). The name "kairuku" means "diver who returns with food" in the Maori language. Fossils of Kairuku grebneffi were first discovered in the Waipara Greensand formation of New Zealand in 2004. The species is believed to have been an excellent swimmer and a primary predator of fish and squid.